EVALUATING RESISTANCE OF JAPONICA VARIETIES FROM TAIHU AREA TO XANTHOMONAS CAMPESTRIS PVORYZAE

Guo Chongjian and Zhang Changping (Plant protection Institute, Jiangsu Academy of Agricultural Sciences) Wang Genlai, Jiang He and Wang Su (Institute of Food Crops, Jiangsu Academy of Agricultural Sciences)

Japonica varieties; Bacterial leaf blight; Resistance

A total of 1,389 japonica varieties collected from the Taihu area were evaluated by clipping method and natural infection for resistance to bacterial leaf blight during 1982-1984. Among them, 281 varieties, about 20.2 per cent of the total, were found to be resistant to various extent. Eleven varieties, namely Tiegenqing, Ailuzhong, Hongmangnuo, Fengjingdao, Daluzhong, Baikewannuo.Xiao'ai 2, Hongkedao, Chang-jienuo, Zaonuodao and Dadaotounuo, were resistant to most isolates ofxanthomo-nas campestris pv. oryzae collected from the Taihu area, and considered of abroad spectrum of resistance. In the experiment, Gaoguonuo and Bangzhumang were resistant to isolates Ks-1-20, Ks-6-6 and Ks-8-4, but susceptible to isolate OS-30. On the other hand,Suvunuo Hukenuo and Xiaoguozinuo showed resistant to isolates OS-30 and Ks-8-4, but susceptible to Ks-1-20 and Ks-6-6. The results indicate that there may exist specific interaction between varieties and isolates.